270 GMC engines used 1 bbl Zenith Carbs.
You can use reducer rings to run a 302 intake ("big port") which has a 3 bolt Stromberg/Holley base pattern and that will get you a 2 bbl Stromberg or Holley that was stock on the 302, or, you cam get a grinder and hog out the mouth of that 4 bolt military intake you have and make an adapter as suggested and run a 4 bbl carb of your choosing. The only 2 bbl bolt on will have to be using the stock intake from a 302. I'm running a Holley AA1 2 bbl on that intake and so is one other person I know on his 270 engine.
Last edited by OldCarKook; 12/24/2014 1:55 PM.
